NT & PT?

[zbang]

I found this switch on top of a junk pile at the back of a shop. Nice thing, about 9" across, it'll look good on the living room wall . It's marked "BARKELEY 30AMP 250V DC & AC" on the switch blades.



The X/Y I understand, and those had 15A fuses; what about P and N (or PT/NT)? N could be neutral, but why a switch for that? How about P?

 

[Jraef]

At one time, likely corresponding to the age when that type of switch was used, it was common to fuse the neutrals.

But, more likely this was for DC, Positive and Negative. No idea on the X and Y though.

 

[zbang]

Hmm, hadn't considered DC. My assumption was a 15 amp AC circuit onto the XC & YC terminals; the others have the marking at the switch, not after the fuse clip. (For PT, my brain went to Potential Transformer, but that's probably wrong.)